Kolvoii UNC1/4-20 Thread Repair Kit, SAE Helicoil Thread Repair Kit with HSS Drill Bits Thread Inserts Taps Break off Installation Tools

I liked everything about it, except I think the tap was a bit dull. I was tapping cast iron and the drill bit supplied walked right through it no problem. But even with tap magic tapping fluid it felt just a bit sketchy. I went slow and got the job done just fine. I would buy one again though.

Most of the time if a hole gets stripped or damaged (if something breaks and say I have to drill it) I just end up moving up a size and then (if needed) for whatever screws into it I put an adapter on it to take it fit the larger size. This is a more clean solution, and as the final threads were factory made it results in a very smooth threaded hole. It does not include the tap wrench so you will need to provide that (don't try to use a drill or similar this is a hand tap and needs to be done slowly and as straight as possible). The kit works well and it gives a very clean and professional look that I don't just get from tapping it myself. This is also great when you really want to maintain the same thread size as original (say you have multiple things to thread into it, or the thing you are threading in is not yours so putting an adapter would be awkward). Overall this is a great idea for repairing a damaged hole. With 25 inserts you are unlikely to ever run out (otherwise how are you getting so many damaged holes!). One other thought is it might be good for softer materials where you are threading something in and out frequently. Normally this would be a ripe time for damaging the original threads given the more malleable material but with this kit you would have their threads actually being the high traffic part so would save that potential wear.

Great storage box! Keeps everything well organized and separated. Each tool is well built, definitely quality tools. Easy to use and functions as expected.

This is an ok helicoil kit. Comes in a box that can fit in your tool chest and has all you will need to install a 1/4-20 helicoil. The drill bit and the thread chaser seems decent enough quality and should do the trick just fine. I have had the name brand kits before and to me these are just as good while being a bit cheaper price.

Overall, quality seems OK, but cheap taps always sketch me out a little bit. However, for the price, you really can't expect too much. I'd say it's worth it if it's not going to be used in a critical application - for something that you absolutely CAN'T afford to have fail, I'd suggest going for a very high-quality kit.